Reaction equation
[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([N:8]2[C:16](=O)[C:15]3[C:10](=[N:11][CH:12]=[CH:13][N:14]=3)[CH:9]2[OH:18])=[N:6][CH:7]=1.[CH2:19]([O:21][C:22]([CH:24]=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)=[O:23])[CH3:20]>C1(C)C=CC=CC=1>[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([N:8]2[C:9](=[O:18])[C:10]3[C:15](=[N:14][CH:13]=[CH:12][N:11]=3)[CH:16]2[CH2:24][C:22]([O:21][CH2:19][CH3:20])=[O:23])=[N:6][CH:7]=1Participants
4
Procedure
6-(5-Chloro-2-pyridyl)-6,7-dihydro-7-hydroxy-5H-pyrrolo[3,4-b]pyrazin-5-one (1.05 g) and ethoxycarbonylmethylenetriphenylphosphorane (1.39 g) were dissolved in dry toluene (30 ml) and the solution was refluxed for 6 hours. After cooling, the solvent was distilled off and the residue was purified by silica gel column chromatography. Fractions eluted with dichloromethaneethyl acetate (2:1) were collected and the solvent was distilled off to give crude crystals. Recrystallization from ether-dichloromethane (5:1) gave 1.2 g of 6-(5-chloropyridyl)-6,7-dihydro-7-ethoxycarbonylmethyl-5H-pyrrolo[3,4-b]pyrazin-5-one.
Workup
- temperaturethe solution was refluxed for 6 hours
- temperatureAfter cooling
- distillationthe solvent was distilled off
- customthe residue was purified by silica gel column chromatography
- washFractions eluted with dichloromethaneethyl acetate (2:1)
- customwere collected
- distillationthe solvent was distilled off
- customto give crude crystals
- customRecrystallization from ether-dichloromethane (5:1)
Sources & evidence
- ORD record
- ord-cc2ffdd26b5e4c0da7999f97296c7bce
- Source dataset
- uspto-grants-1989_11
- Patent number
- US04879293
Linked notes
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